A switching regulator may be configured to provide an output voltage (Vout) in response to an input voltage (Vin). Typically, a switching regulator includes an inductor that is coupled to a switch. In operation, the inductor current is a triangle wave current based on the opening and closing of the switch, and an output capacitor provides Vout from the inductor current. Also, the switch is controlled by a control signal, where the duty cycle or the frequency of the control signal is typically modulated based on negative feedback.
In a pulse width modulation (PWM) scheme, pulse width modulation is typically employed based on Vout, so that the on-time of the switch is modulated. In a constant on-time (COT) scheme, the on-time of the switch is relatively constant, and the off-time of the switch is modulated. Unlike the PWM scheme, a COT scheme typically does not need compensation. Also, a COT regulator typically has a relatively fast transient response.